Ensemble-Based Simultaneous State and Parameter Estimation in a...

Monthly Weather Review;  October 1, 2006 ;     700+ words ......parameter estimation where the source of model error is the uncertainty in the model parameters...of the atmosphere. Commonly known as model error, this divergence usually arises from...imperfect initial conditions, influences of model error on the structure and propagation of...

The Role of Scales in the Dynamics of Parameterization Uncertainties

Journal of the Atmospheric Sciences;  June 1, 2006 ;     700+ words ...ABSTRACT The dynamics of model error due to parameterization uncertainties...atmospheric dynamics, known as model error (Leith 1978; Klinker and Sardeshmukh...1999). Recently, the dynamics of model error in low-order nonlinear deterministic...

A general weak constraint applicable to operational 4DVAR data...

Monthly Weather Review;  September 1, 1997 ;     700+ words ......presented. The proposed definition of the model error has a flexible time resolution for the...a 4DVAR method. The inclusion of the model error term, even only the systematic error...forecast models are not perfect. The model error should be taken into account if a sophisticated...

Ensemble Forecasting in a System with Model Error

Journal of the Atmospheric Sciences;  May 1, 2005 ;     700+ words ......complicated, and the effect of model error on ensemble performance is not clear. In this paper, the effect of model error on ensemble behavior for a version...and help reveal the effect of model error on ensemble performance. Comparisons...

Accounting for the Error due to Unresolved Scales in Ensemble Data...

Monthly Weather Review;  November 1, 2005 ;     700+ words ......Insufficient model resolution is one source of model error in numerical weather predictions. Methods...ensemble-based data assimilation to deal with model error. Two general methods, "covariance inflation...were considered for parameterizing the model error at the resolved scales ...

Tests of an Ensemble Kalman Filter for Mesoscale and Regional-Scale Data...

Monthly Weather Review;  April 1, 2007 ;     700+ words ......10-13 June 2003. The significance of model error in both warm- and cold-season events...dropped in real-world studies where model error is caused by inadequate parameterization...other random errors. The presence of model error can often result in both a large bias...

Predictability

Bulletin of the American Meteorological Society;  December 1, 2005 ;     700+ words ......emerged at the forum. First, we consider model error and initial-condition error, given that...concepts and results. INITIAL-CONDITION AND MODEL ERROR. Although model and initial-condition...face initial-condition uncertainty. Model error is equally unavoidable for complex systems...

Distributed Forcing of Forecast and Assimilation Error Systems

Journal of the Atmospheric Sciences;  February 1, 2005 ;     700+ words ......unstable system addresses the effect of model error on forecast error in the presumably...addresses the effect on the assimilation of model error in the presumably stable data assimilation...as a stable observer. In this study, model error refers both to extrinsic physical error...

Atmospheric Data Assimilation with an Ensemble Kalman Filter: Results with...

Monthly Weather Review;  March 1, 2005 ;     700+ words ......assimilation cycle is mainly due to model error. An isotropic parameterization, similar...variational algorithms, is used to represent model error. After some adjustment, it is possible...winds and temperature. Currently, no model error is added for the humidity variable...

Assessing uncertainties in WEPP's soil erosion predictions on rangelands....

Journal of Soil and Water Conservation;  September 1, 1995 ;     700+ words ......simulations. Typical questions are: Is model error or parameter error decreasing or increasing...with a variety of factors including the model error, caused by the abstraction of a physical...by a set of mathematical equations. Model error - also known as structural error - arises...

Short-term dynamics of model errors

Journal of the Atmospheric Sciences;  September 1, 2002 ;     700+ words ......this paper, the short-term dynamics of model error is examined in the context of low-order...local Lyapunov exponents and of the model error source term along the dominant unstable...that depending on the nature of the model error sources (here limited to a white noise...

PREDICTABILITY, OBSERVATIONS, AND UNCERTAINTIES IN THE GEOSCIENCES

Bulletin of the American Meteorological Society;  September 1, 2007 ;     700+ words ......disciplines and applications. Interestingly, model error and parameter estimation were quickly...Environmental Prediction (NCEP)] suggested that model error can be accounted for by "remapping...pointed out the following two types of model error: a parametric error and a space ...

Resilience of Hybrid Ensemble/3DVAR Analysis Schemes to Model Error and...

Monthly Weather Review;  May 1, 2004 ;     700+ words ......the robustness of hybrid schemes to model error and ensemble inaccuracy in the context...the 3DVAR scheme. In the presence of model error a perturbed observations hybrid and...assimilation schemes in the absence of model error.1 However, there is less literature...

Long range forecast for 2000; South-west monsoon season rainfall.

M2 Presswire;  May 25, 2000 ;     700+ words ......its long period average. The estimated model error is of the order of +/- 4 . However...forecast error has been larger than the model error, primarily because the statistical relationship...Regression Models with an estimated model error of +/- 8 , have been used for generating...

The Future of Medium-Extended-Range Weather Prediction: Challenges and a...

Bulletin of the American Meteorological Society;  May 1, 2007 ;     700+ words ......the initial condition uncertainty and model error have remained at the forefront of ongoing...errors. Additionally, the dependence ot model error on the forecast state must he better...in order to more fully characterize model error. Acknowledging (he uncertainties in...